Sydowia 74 (2022) 33 DOI 10.12905/0380.sydowia74-2021-0033 Published online 21 June 2021 Glomeromycota in Mexico, a country with very high richness Martin Hassan Polo-Marcial 1 , Luis A. Lara-Pérez 2 , Bruno Tomio Goto 3 , Xochitl Margarito- Vista 3 & Antonio Andrade-Torres 4. * 1 Doctorado en Ciencias en Ecología y Biotecnología, Instituto de Biotecnología y Ecología Aplicada, Universidad Veracruzana, Av. De las Culturas Veracruzanas No. 101, Campus para la Cultura, las Artes y el Deporte, Col. Emiliano Zapata, C.P. 91090, Xalapa, Veracruz, México. 2 Tecnológico Nacional de México, Instituto Tecnológico de la Zona Maya. Carretera Chetumal-Escárcega km 21.5 Ejido Juan Sarabia, C.P. 77965 Quintana Roo, México. 3 Departamento de Botânica e Zoologia, Universidade Federal do Rio Grande do Norte, Campus Universitário, 59072-970, Natal, RN, Brazil. 4 Instituto de Biotecnología y Ecología Aplicada, CA 173 Ecología y manejo de la Biodiversidad, Universidad Veracruzana, Av. De las Culturas Veracruzanas No. 101, Campus para la Cultura, las Artes y el Deporte, Col. Emiliano Zapata, C.P. 91090, Xalapa, Veracruz, México. * e-mail: aandrade@uv.mx Polo-Marcial M.H., Lara-Pérez L.A., Goto B.T., Margarito-Vista X. & Andrade-Torres A. (2021) Glomeromycota in Mexico: a country with very high richness. – Sydowia 74: 33–63. The biogeographical species list based on data compilation represent a powerful tool to understand fungal diversity distribu- tion. After fve decades of extensive studies on arbuscular mycorrhizal (Glomeromycota) diversity we compiled a checklist with 160 species recorded in Mexico based in 95 publications. The richness found represents 49 % of species, distributed in 34 genera, 13 families and fve orders in Glomeromycota. The genera Acaulospora and Glomus were dominant, with 27 and 26 species, re- spectively. The most represented spore development type was ectocarpic species (72 %) followed by glomerocarpic (28 %). The vegetation type with the highest species richness was agroecosystems (135 spp.), followed by xerophytic shrublands (74 species). Low number of species were recorded in aquatic and underwater vegetation (38 spp.) and coastal sand dunes (28 spp.). The Jac- card similarity index varied from 0.32 to 0.66, indicating a low to medium level of overlapping in AMF species between vegeta- tion types in Mexico. More effort should be carried out on ecological and morphological studies of a larger geographical scale mostly in priority areas or less-studied vegetation types to better understand species distribution and to increase the number of AMF species that may still be discovered in Mexico. The inventory allows the defnition of strategies for future studies in Mexico, a very biodiverse country, aiming to expand knowledge of AMF distribution as well as allowing the description of new taxa. Keywords: distribution, ecology, mycorrhiza, taxonomy, vegetation types. The phylum Glomeromycota (Schüssler et al. 2001, Tedersoo et al. 2018, Wijayawardene et al. 2020) comprises the arbuscular mycorrhizal fungi (AMF) that form mutualistic and obligate symbiotic associations with around 80 % of vascular plants (Wang & Qiu 2006, Brundrett & Tedersoo 2018). The AMF represent one of the most important biological components of the soil microbiota in natural and agronomic ecosystems worldwide (Moreira & Siqueira 2006). Symbiotic interactions with AMF regulate and maintain plant biodiversity and plant species composition (van der Heijden et al. 2015). This is because the extraradical hyphae facilitate nutrient uptake, in change for carbohydrates and lipids (Smith & Red 2008). Due to their multiple benefcial effects, AMF have gained considerable attention in sustainable agriculture, restoration programs and evolutionary relationships in differ- ent plant groups (Wang & Qiu 2006). So far, 330 spe- cies of AMF have been described and are currently classifed in three classes, fve orders, 16 families and 48 genera (Goto & Jobim 2019, Wijayawardene et al. 2020). Of these, Geosiphon pyriformis (Kütz.) F. Wettst. is the only representative of this phylum that forms associations with cyanobacteria of the genus Nostoc (Schüssler 2012). Mexico harbours around 12 % of the species bio- diversity worldwide and is ffth in the list of coun- tries with the most endemic plants. It has a wide territorial expansion (1, 972, 550 km 2 ) (CONANP 2018, Mittermeier et al. 2004), topography with an altitudinal gradient, contrasting climates and geo-